It's something Charlie Sheen has, apparently. Do you? A handy guide.

Is Charlie Sheen a tiger? No. At least not as far as we know. But the actor has compared himself to a tiger on more than one occasion, telling the Today show's Jeff Rossen that he's got "tiger blood" and that it makes him impervious to the dangers of addiction:

When asked by Access Hollywood what the hell that means, Sheen said, with some amount of frustration, "I don't know. It's blood that flows through me that I can feel." The he tweeted about it, and the Twitter people seem to be having fun with that.

Advertisement - Continue Reading Below

So what is tiger blood, exactly? It's just the blood that happens to run through a tiger's body. Oh, and it's also the name of a brand of anabolic steroids used to build muscle.

But what's so special about actual tiger blood? Nothing, actually. It's basically the same as the blood in any other animal. "Tiger blood is just blood," says Luke Hunter, the executive vice president of Panthera, a wildcat conservation group, also sounding a little frustrated. "It doesn't have any unique qualities that make it any different from human blood." So, in that sense, maybe we're all a little bit like tigers. And Charlie Sheen.

More From Esquire

Then why the whole "tiger blood" thing? It might have something to do with the fact that tigers are bloodthirsty carnivores who don't tend to lose a lot of their own. "They live on stalking and killing other wildlife species," says Mahendra Shrestha, director of the Save the Tiger Fund. "Deer, pigs, wild cattle like buffalo, gaur, banteng, and sometime more unusual animals, like calves of rhino and elephants." In other words, tigers are very strong. Stronger than Charlie Sheen.

Are Charlie Sheen and tigers similar in any way? Tigers are hunted by poachers who threaten to make the species extinct in its natural Asian ecosystem. Charlie Sheen, too, is feeling a little hunted lately, telling Rossen that CBS, the parent of his suspended sitcom, is "trying to destroy my family." Somehow we doubt Sheen is trying to drum up sympathy by comparing himself to an endangered animal, but if he is, he's certainly not far off the mark.

How do the tigers feel about all this? Not great, probably. At least the people who care about tigers don't seem very happy about the comparisons. When we first e-mailed Luke Hunter, he told us, "It's so bizarre and such a distraction it's really not worth the time to chat. Charlie Sheen can talk all he wants about having tiger blood, but the sad truth is illegal poaching around the world is putting this magnificent creature at serious risk of extinction in the wild. Comments like Sheen's do nothing to help save tigers." They also don't seem to be doing very well for Charlie Sheen. We think.